Myocardial performance index correlates with right ventricular ejection fraction measured by nuclear ventriculography

Background: Assessment of right ventricular (RV) ejection fraction (EF) by two-dimensional echocardiography (2D ECHO) is practical but limited because of complex geometry of the RV. Techniques used for accurate measurement of RV EF are invasive or costly. However, derivation of 2D ECHO Doppler parameters to estimate RV function could be useful and inexpensive. Methods: RV EF measured by nuclear ventriculography was compared with 2D ECHO estimates of myocardial performance index (MPI) and peak tricuspid annular systolic velocity (PTASV). Linear regression analysis and sensitivity analysis were used to analyze the data. Results: RV EF measured by nuclear ventriculography correlated with MPI significantly (r = -0.55, P = 0.005) but not with PTASV (r = 0.09, P = 0.69). Using abnormal RV EF < 45% measured by nuclear ventriculography, the sensitivity and specificity for MPI > 0.50 were 45.4% and 100%, respectively. The sensitivity and specificity of PTASV <= 17.25 cm/sec in detecting abnormal RV EF were 100% and 35.4%. Conclusion: MPI greater than 0.50 indicates that RV function is abnormal and a value of PTASV > 17.25 cm/sec indicates normal RV function.